Friction gearing



Sept. 17, 1935, 1Q', ALMEN -FAL 2,014,920

FRICTION GEARING Filed May 5l, 1932 5 Sheets-Sheet l Sept. 17, 1935. .1.0. ALMl-:N ETAL FRICTION GEARING Filed May 3l, 1952 3 Sheets-Sheet 2 e @a y ea W 39. mdfa gaf] or ,www l c N Q, i| /W v .mm Y, n N M. A F v. n m. l \w\ .mm n u l Q5 .,NHKH mu "Mm Q 1|, .QQ Rkw mw .Q Mm i E m w S a. v l E Nw. E M M w 3S m m Sept. 17, 1935.- J. o. ALMEN AL FRIGTION GEARING Filed May 3l, 1952 3 Sheets-Sheet 3 'Patented sept. 17, 1935 John 0. Almen,

and Winfield D. Gove,

by mesne assignments Delaware poration, Detroit, Mich.,

Royal Oak, and Jacob Ehrlich Detroit, Mich., assignors,

to General Motors Cora corporation of vApplication May 31, 1932, Serial No. 614,332

14 Claims.

The invention which constitutes the subject of this application is an improvement in a variable speed transmission mechanism employing a plurality of races or discs having toroidal raceways and interposed friction rollers. The invention has been designed primarily for use on motor J vehicles.

The essential objects sought-for in prior known transmissions of this kind, such as the provision of an overspeed drive made possible by-the tilting of the rollers in both directions from their normal position in which' they give a l'1:1 ratio; the provision for neutral and reverse driving by the use of a reversing gear transmission between the engine and the friction transmission; the automatic control ofthe pressure upon the rollers by the driving torque and many other advantages are among the objects of this present invention. Certain additional advantages are attained by the subject matter herein disclosed. Among them are the following:

1. An improved mounting ofA the follower or secondary rollers whereby for reverse roller rotation the mounting is such as to reverse the direction of the imparted inclination. Specifically this object is attained by novel structure wherebydiierential friction in the roller mounting automatically determines the position of the movable element in th mounting.

2. An improved mounting for the master roller adapted for a transmission wherein the tilting of the master roller operates positively to tilt the follower rollers without resort to torque equalization.

3. An improved mechanism operated automatically by reversing the direction of rotation of the driving mechanism to reverse the direction of inclination of the master roller produced by an externally applied force. Specifically this is accompanied by a sliding or tilting\control block,

the movement of which is effected by a reversed rotation of the output shaft and the( changed position of which causes the direction of inclination of the master rollerto be reversed when a predetermined external force is applied to the block. structurally the invention also comprises novelty in the provision of a coil spring and sleeve reversing vmechanism associated with the output shaft and stop mechanism associated therewith. 4. An improved bearing for the roller carriers. 5. A novel connection between the driving disc and its connection with the input shaft occasioned and made possible by the use of the supporting spider yfor the roller carriers as the locating means rather than by using the input shaft for that purpose as in certain prior proposed constructions.

6. The operation of the master roller upon the follower rollers through the instrumentality of a central sleeve provided with gears. A'

(Cl. 'I4-200) 7. The provision of suitable stops to limit the extent of tilting.

8. An improved means to control the rate of ratio change under th'e inuence'of a governor or other externally applied force.

9. An improved means whereby a quick shift down to low speed is attained, preferably fendered automatically operable by the action of brake application.

10. An improved'` device whereby ratio at any one timey ator. l

Other objects and advantages will be understood from the following description. In the drawings accompanying this description, Fig. 1 is a top plan view, partly broken away and in section. k

Fig. 2 is a view in vertical section. Fig. 3 is a view as seen from line 3-'3 of Fig. 2. Fig. 4 is an end elevation, partly in section, 20 showing the operating mechanism for controlling the master roller. Fig. 5 is a longitudinal section through the auxiliary housing containing the dashpot mechanism.` 25 Fig. 6 is-a perspective of`parts in disassembled relation.

Fig. 'I is a perspective of the reversing mechay nism shown in Fig. 2 with the parts disassembled.

Fig. 8 shows certain parts in perspective and in 30 dissassembled relation.

Referring by reference characters to the drawings, numeral 9 is a housing for a main clutch and I- reversing gear. Noinvention is herein claimed for any specific clutch, and any preferred 35 type of reversing gear may be employed. A fork I3 is rocked by the movements of a ring I2 reciprocated by a governor, not shown, which is operably associated with the input shaft of the transmission. 'I'he fork is pivoted on pin I4 40 carried by a rocking member I6. The pin Il is eccentrically positioned relative 'to the trunnions I8 about which the member I6 rocks. A rod I1, extending toward the rear of thetransmission, is connected to from the fork member I3. If the member I 6 be assumed to be held in position therotation of fork I3 about the axis of Il as influenced by the governor operates through the arm 20 to push or pull the rod I'l and thereby to change the 50 the speed- 10 is indicated to the oper- 4speed ratio of the transmission as will be explained below. On the other hand if the governor is holding the fork I3 xed, a manually operated rotation of rocking member I6 (for example by turning an extension I 6l of the journaled axis I8) 55 will cause a bodily movement of the pivot axis Il and thereby rock the fork about its connection with ring I2. This, too, will reciprocate rod Il and change `the speed ratio.

The input shaft I5 is connected to the driving 60 an arm 20 extending 45 collar 5| is supported on a hub disc I9 by a cup-shaped member 22 secured to the disc I9 by a sliding non-rotatable connection as shown in Fig. 2. The driving disc rotates on a hub 2| constituting a part of a double spider. At each end of the hub the spider is formed with diverging arms, these arms at one end being represented by numerals 23, 25, and 21 on Fig. 4. These arms are suitably secured to the casing as at 29. At 3| is shown the driven shaft having at its front end a pilot bearing 33 in the end of the input shaft I5, and a flange 35 secured to a rst driven disc 31. Shaft 3| extends through thel hub 2| and 'near its rear end there is mounted freely thereon a second driven disc 39. At the rear end of the shaft 3| is a anged nut 4| threaded on the shaft. The front end of the nut engages the hub of a collar 43 non-rotatably but slidably mounted on the shaft. A disc-like spring 45 engages a shoulder on the collar and also engages the periphery of disc 39 to push the disc 39 forward and to pull the disc 31 (through the instrumentality of the collar 43, nut 4|, and shaft 3 I) toward the rear thus holding the rollers under pressure between the discs. There is a spline and grooving connection interlocking the disc 39 and the collar 43 as shown at l45. This connection, together with the splined' connection of collar 43, on the shaft 3|, permits the necessary slight axial movement of the disc 39 but prevents any rotation of disc 39 relative to the shaft. Adjustment of the collarl 4| on the shaft operates in an obvious manner to determine pressure resiliently applied between thev rollers and the discs. Torque-loading rollers 49 mounted-inv openings in the collar 43 engage inclined surfaces on the disc 39 and a spacing collar 5| (the inclined surfaces are shown by numeral 52). The portion of collar V43 and has a radially splined connection as at 53 `with a ange 52 of a universal joint member `55. Between the flange 52' and a radial ange 54 on the nut 4| which engages the universal joint member 55, there is a thrust bearing 51. It will the torque-loading rollers. `avoid looseness when the device is not under load.

be seen that th engagement of the flange 52 with the hub of nut 4| and the engagement of flange 54 of the nut 4I with the inner surface of the joint member 55 serves to properly position the universal joint in such a way as to prevent anything but axial thrusts being delivered by this joint member to the transmission. Around the outside of the universal 4joint member 55 and within the casing are conventional bearings 6|. A flat spring 60 located as shown is in series with Its function is to 'Between thedisc I9 and each of the discs 31 and 39'are the friction rollers, one of which is designated at 63 on Fig. 2. The several rollers engage the toric raceways of the disc. The adjustment ofnut 4| controls the normal pressure between the discs and rollers. Heavy torque operates through the rollers 49 and the cam surfaces 52 to add pressure between the discs and rollers and prevents slipping.

Surrounding the shaft is a tubular ring member 63'-. Welded or otherwise secured to this ring yat oneend is a gear 65. `A gear member61 is splined to the otherend of ring 63'. An abutment member 69 engages the gear 61 on one side i,and is supported on shaft 3|. The other side of gear 65 engages the xedly supported spider as shown. The member 69 is connected to the spider by a spacing and fastening means 1|. In this way the gear members 65 and 61 are mounted in definite relation to the 3| and within hub 2| .c

f pin 9|, 1S not fixed in the position shown.

' spider. This is important because the roller carriers,.referred to below, have gear elements in mesh with gears 65 and 61, and these roller carriers are mounted on the spider. In this way the 63. The rollers of each set are angularly spaced.

Eact set in the embodiment illustrated has three rollers spaced at angular intervals of 120. The rollers of the two sets are similarly disposed so that the same radial planes include the centers of both sets. Numeral 63 is used to designate the five so-called follower rollers. The roller marked 13 is the so-called master roller since its function, in addition to serving as the driving roller,

is to control the driving ratio position of the several rollers marked 63. y

Each roller is mounted in a carrier.' The carriers for roller 63 are designated by numeral 15.

These carriers are provided with or formed integral with gear elements 11 which mesh withl the gears 65 or 61 as the 4case may be. The carriers are mounted at their ends in the spider arms as shown in Fig. 4. The mounting permits the carrier and its roller to assume positions for driving at varying speed ratios. Such angular positionsmaybeconsidered as due to the rocking of the carrier and the roller abouty the pivotal connection between the carrier and the spider. This rocking movement which produces changes in driving ratio is called ti1ting. In opposite spider arms is a hollow plug 19 held from rotation by a pin 8|. A spherical cap 83 is fitted to the inner end of each of the plugs 19, the polar end of which spherical cap provides what is substantially a point contact as at 85 in the bottom of a pocket 84 formed in the carrier. The wall at the outer end of the pocket surrounds the base of the cap. Preferably the cap is somewhat more than the hemisphere and'contacts with the wall of the pocket along a circumferential line. As a result of this construction the bearings permit such a rotation of the carrier as is adapted to produce a tilting of the roller to effect changes in gear ratio.

The mounting of the rollers 63 in the carriers 15 is next to be described. The roller 63 is rotatably supported by a sleeve 81. This sleeve has an opening rectangular in section extending therethrough. Through this opening extends a similarly shaped but unequally dimensioned pin `lar in section. One end 90 fits in a similarly shaped opening in the gear element 11 of the carrier. The other end 92 is rotatably supported in a plug 93 inserted into a round opening in the carrier and held thereby by a pin 95. This construction permits the insertion of the pin 89 through the carrier opening. A pin 9| extends diametrcally throughpin 89, its ends being supported in sleeve 81. This pin is inclined to a line joining the points of contact between the roller and the discs, and also is inclined to the long axis of the carrier. These lines are marked c-c and df-d on Fig. 1. Preferably the angular position of the pin locates it midway between the lines d-d and c-c. The pin 89, which carries n This rectangular portion extends lshifted to the other by a reversal .the discs and rollers.

. and disc.

may swing through an angle of 90. Means are provided to limit its swinging movement in each direction. The plug 93 has segmental parts 99 (see Fig. 3) which may be engaged by the at surfaces |00 or\ |02 on each end of a ,part 91 of the pin 89 between its rectangular intermediate part and its end circular part. It is intended that the pin 89 shall be in oneor the lother of its two extreme positions when the rollers are rotating. vWhen. it is in oneI position it may be of rotation of This takes place as follows: It will be seen thatthe radius of the ends of pin 89is less than the radius of the sleeve about which the vroller turns. In consequencef the friction at the latter surface, due to the roller turning about the sleeve, overcomes the friction at the ends of the pin 89 in its bearings and rotates the sleeve and with it thepin since the sleeve hasa non-rotatable mounting on the pin to its 'opposite limiting position, the position, for example, wherein faces |02 engagethe parts 99, The result of thusI reversingv the position of the pin 89 is tof'reverse the position of the inclined pin 9| to the end that opposite inclinations may be imparted to the roller when the roller is rotating in .Oppositedirections to thereby permit the same ratio changes being made regardless of the direction of driving for the same sense of external control action.

yThe above described movements of thefsecondnaryrollers are accomplished by the tilting movement of the carrier |0|, the carrier of the master roller 13. This carrier |0| is mounted in opposite arms of the spider just as are the carriers 15 for the follower rollers/ The carrier |0| is provided with a gear |03 which meshes with gear |35. When the carrier is rocked in its bearings its gear element |03 rotates gear 65 and with it sleeve 63' and gear 61. .In this way the follower` rollers are all inclined to the same extent. A plug |05 is inserted in a circular opening |01 in carrier 0|. It is externally of circular outline and is designed to fit a similarly shaped opening in the carrier, but it has flat surfaces |09 on opposite sides. It has a reduced upper end which is dsecured by a pin to the wall of the carrier. The plug has a. central opening to receive the upper'end of pin 3. The other end of pin ||3 is received within an opening of the gear portion of the carrier. The element I3 is pivoted to thesleeve I5 by pin ||1 as shown in Fig. 2. The sleeve ||5 rotatably supports the master roller 13. This sleeve extends upwardly through the carrier occupying the region within the circular opening 01 provided by the fonmation ofrthe flatV surfaces of the plug. At its upper extremity it is attached to a control rod ||9 by a connecting pin'|2|. The external surface of pin ||3 is rectangular except at the ends where it is mounted in the carrierandplug.

through a similarly shaped opening in the sleeve ||5 but with clearance to permit the sleeve and roller to rotate about an axis b-b, Fig. 1, this axis being the line joining the points of contact between the roller As a result of this clearance, movement imparted to the sleeve by the rod ||9 is operable in a Way' to be explained below to inoline the roller 13 about the line bb. 'Ihere then follows a movement of the roller and sleeve due to its direction of driven rotation and to its inclinationwhich restores the roller to a position d in which an angular position is assumed to produce a new driving ratiov and in which also the axis of rotation againv intersects the main axis of lhas an offset end |3| with arms |3 ^site faces tapered recesses as at.

lwardly directed arm I5 vprojecting inwardly to engage and limit the which carrier rotation rocks the gear 65, sleeve 4|53', and gear 61, thereby similarly effecting new driving ratios in the case of rollers.

The above described inclination of sleeve I5 is brought about by the following mechanism in'- cluding the rod y|| 9 already referred to. This rod has a head |25 with flanges |22 and |23.. Between these anges are received extremities of the ends of the sleeve 5. The rod ||9 has a. slot |29 for a purpose to be described. It also 3 carrying ta7 pered pins |35. A control block |39 has on oppo- |31 to receive the tapered pins |35. One face of the block has a pin |4|. The ends of the block are provided with slots |43, each slot having two parts of unequal transverse dimensions. The portions of the slots having equal dimensions are at the corresponding ends of the end faces. Secured to the main housing is a small housing |58. This housing has a wall |59 provided with a rotatable bearing support for a shaft |53. Adjacent its other' end shaft |53 has a'second bearing 6| in a partition of the small housing. Shaft |53 has a flange |5| from whichextend radial arms |49 carrying spherical members\\|41 and |41' as shown. From flange u| 5| therejextends an up- 5 provided with a pin |51. is connected to pin |51.

each of the follower A rod |63 (see Fig. 1)

. Rods |63 and |1 are united by a housing |65 enclosing springs whereby a resilient push or pull may be imparted to eifectrotation of shaft |53 either from the action of the governor or by a force applied to rotate the journal extension |61 of pivot member I8. Such a rotation of shaft |53 through the reciprocationof rod |63 is intended to change the driving ratio through the instrumentality of the control block and rod ||9 as will be explained below. V

For the purpose of reversing the direction of Vinclination imparted to the roller 13V when its driving direction is reversed, the following expedient is employed.4 A coil spring embraces shaft 3|. It has at one end a relatively short radial arm |19 and at its other .end a somewhat longer radial arm |8|. The spring is encompassed by a sleeve |11.

45 |15 snugly It also has an operating arm |95 projected radially. A tubular shaped member |85 encloses the sleeve |11 and the spring when the lattr is assembled within the sleeve. 'I'his member |85 55 is provided with a ange |81 which is secured to the spider by fastening means |89. The member |85 has a slot |93 through which the arm |95 extends and the end walls of which slot limit the rotation of the sleeve |11 by engagement 60 with the arm |95. A pin I9| projects inwardly and radially from the member |85 and lies in the path of the rotary movement of the end |19 of the spring |15 as it rotates with shaft 3|. 'Ixhis member |85 also has a radial flange |99 65 1nward axial movement of thesleeve |11. 0n the end of vmember 85 is a slot 200 through which the spring end |8| also extends. If `the shaft 3| reverses its direction of rotation and starts to turn in the direction of the arrow (Fig. 7) the spring end |19 first engages the Y end of the slot |91. The resistance to rotation on the part of sleeve |11 (owing to the parts operatively connected therewith) makes of this engagement a The sleeve has at 50- one end a slot |83 and at its other end a slot |91.

' momentary anchorage for the right end of the spring. The rotation of the shaft servesto wrap the spring and so contract it that it grips the shaft 3| and rotates with it and carries the sleeve |11 until the arm |95 engages the end of the slot |93. Thereafter the spring end |8| engages the Z end of slot 200 in |85 as a positive stop and the action of the spring ceases and relieves the grip of the spring on the shaft. In a similar way reverse rotation of the shaft causes the spring to reverse the direction of rotation of the sleeve |11. 'I'he end |8| engages the X end of the slot |83 of sleeve |11, thus affording a momentary anchorage. The rotation of the shaft as before wraps the spring |15 on shaft 3| and causes it to rotate the sleeve |11 to its limiting position. The pin |9I constitutes the limiting stop for the spring whereby it is rendered inoperative.

The reversing rotation of collar |11 is imparted to the control block by the following mechanism.

A shaft |1| projects from the open end of the spider carried plug 19'. Shaft |1| is supported at its other end by a portion of the spider. Slidable on the shaft |1| is a collar |69. To permit reciprocation ofthe collar on the shaft |1| and to prevent rotation of said collar there is a pin 203' projecting from the collar and extending through the opening |29 of the control' bar H9. Pivoted to the spider is a double arm lever 203.

One arm of the lever engages between the anges of the collar Y|69 in such a way that rocking of the lever shall reciprocate the collar. An adjustable link 20| connects the other arm of the lever 203 to the end of arm |95 on the sleeve |11. A link |13 connects thecollar |69 with the pin lll on the control block |39. As a result of this construction the rocking of arm |95 on the sleeve |11, whenever the direction of rotation of the shaft is reversed, operates through the instrumentality of link 20|, lever 203, collar |69, and link |13 to rock the block |39 and to thereby shift one of its slots to an inoperative position relative to its cooperating spherical member |41 and |41', and toz shift the other slot so that its narrow kpart is brought into operating relation to the spherical member with which it is associated. In this way one direction of rotation of shaft |53 produces oppositeY directions of inclination for opposite rotary movements of shaft 3|, a condition necessary to cause subsequent restoration movements such as to effect the same ratio changing tilt regardless of whether the vehicle is being driven forwardly or rearwardly.

The shifts to higher and lower ratios need to be controlled to prevent too rapid changes as influenced by the governor or by forces applied to shaft |61. To this end the housing |58 is formed with a cylinder 2|3 within which reciprocates a piston 2|| carried by a rod 209, this rodbeing connected to an arm 201 secured to shaft |53. This piston and cylinder construction is intended to constitute a dashpot to control the rate of ratio changing. The edge of the piston is preferably rounded as shown to make a snug t at all times regardless of the angular relation of the parts 201 and 209. The piston has a restricted opening 2| 5 for the passage of uid in the cylinderV from one side to the other of the piston. There is also a bypass 2H communicatlng with the cylinder at a midposition and also with the lower-end of the cylinder. In the bypass is a spring-pressed valve 2|9 operable to close and prevent the passage of fluid as .the piston moves downwardly from its mid position in the direction corresponding to lower driving ratios. A rod 22| is mounted to reciprocate in a passage in alignment with the bypass'passage. This rodmay engagev and depress the valve member 2 I9 so that the bypass together with the opening 2|5 provide for freepassage of fluid from below to above the piston. For the purpose of reciprocating rod 22| a rod such as 223 may be provided to reciprocate at right angles to rod 22| Rod 223 may have a tapered end to engage and move the rod 22 Any preferred means may be used to actuate this rod 223. When stopping the car with the brake it is very desirable that the piston in the dashpot 2|3 should not delay the shift to low speed. It may be well therefore to connect the rod 223 to the brake hook-up so that the application of the brake may be accompanied by an opening in the bypass to permit a quickshift to low speed. Anyconvenient method may be adopted for that purpose. In Fig. 1 has been shown a lever member 30| engaging the rod 223 and suitably connected to any conventional brake hook-up designated as 303.

It may be desirable to provide on the instrument-board a suitable instrument to indicate the prevailing speed ratios. Such instruments operated by rheostats are well known. There is shown in connection with this transmission a suitable operating connection for such an instrument. Within cover member 231 is provided a substantially conventional rheostat employing a coil 305 and a contact arm 301. This contact arm is carried on the end of a shaft 221 mounted in a bracket 229'. On the end of the shaft 221 is a gear member 229 which is in mesh with a gear member 23| carried on a tubular shaft member 233. This shaft member is secured by fastening means 235 to the end of shaft |53 as shown in Fig. 4. In this way the rotation of shaft |53 operates through the gearing elements and the rheostat'to' give visible indication of the existing gear ratio which is determined by the angular position of shaft |53. For the purpose of limiting the rocking of the carriers a suitable abutment may be provided on the carrier and spider as represented by numeral 3|5 on Fig. 4. Also, to limit the rotation which may be imparted to shaft |53 an abutment 3|1 may be added to the wall of the secondary housing |58, this abutment to be engaged by an adjustable screw member 3|9 carried by an arm on the shaft |53, which may, if preferred, constitute an integral part of arm 201. f

In the operation of the device the power from the engine rotates through the clutch and gearing in housing 9 to rotate the input shaft I5 in either a forward or reverse direction. As in constructions of this kind the gearing in box 9 may be placed in neutral, in which case no drive is transmitted vthrough the transmission. Rota- `tion of shaft I5 rotates the disc |9 which l'tter operates through roller 13 and rollers 63 to drive the driven disc 31 and 39. The drive of these discs is transmitted to the driven shaft 3|. Nor-.

to change the ratio from low speed toward higher sleeve ||5 tends to rock the sleeve and roller in a direction to change the speed ratio. This is in eiect a tendency to rock these parts about the line a-a, Fig. 1. Such tendency meets with considerable resistance for the reason that such a movement involves sliding friction between the rollers and discs. The pressure of the spherical member on the block may, however, be considered as -a pressure operating to rotate the roller and its sleeve about the line bwhich is the line joining the point of contact between the roller and the discs. Clearance has been provided between the roller sleeve and the'pin 3 so that such a movement may occur. This movement therefore which involves overcoming less resistance is the movement initially imparted to the roller and is described by the term inclination. This inclination deflects the roller axis from intersection with the main axis and if uncheckedy would cause the roller to leave the disc.

This position `of the roller associated with the normal driving rot-ation causes the roller to describe a spiral path as a result of which it assumes a new position in which its axis intersects the main axis and in which it assumes a new position 4of tilt-a new driving ratio. Accompanying this spiral movement of the roller the carrier rotates to the new planeA of the roller. As the'carrier rotates it rotates gear 65, sleeve 63', and thegear 61. The follower rollers are then changed to new driving ratios as follows: The roller 63 of Fig. 2 may be taken as an illustrative example. The rotation of gear 61 rocks the roller carrier 1'5 in a direction of tilt, that is aboutaxis d-d. This rotation is not accompanied by a tilting of the roller because of the I #resistance which would result from the sliding friction. Since the pin 89 is anchored at its end in the carrier it tilts with the carrier. 'Ihis movement of the carrier and p in 89 relative to the sleeve and roller is permitted bythe clearance between the pin and sleeve. The pin 89 carries bodily the inclined pin 9|. Since the ends Vof pin 9| are onopposite sides of line d-d one end of the pin is depressed below and the other en d raises above the plane of the paper (Fig. l)

" as the carrier with its pin 89 is rocked. These forces acting upon the pin 9| pushing one end below and pulling the other endabove the plane of the paper may be considered as operating to turn the roller about the line c-c joining the points of contact of the roller with the discs. vThis is preciselyl the action which takes place. The tiltingof the carrier results first in an inclination of the roller, which inclination associated with the driving of the roller causes the roller to describe a spiral path and assume a new driving ratio position.

If now the direction of drive is reversed, each disc and roller has its rotation reversed. In order to secure the same ratio-changing eiect through inclination and tilt 'the inclination of the master Aroller must be reversed. 'I'he reverse rotation of the master roller associated with a reversed inthe piston through vparted L to the follower dent and requires no explanation.

of the ball members |41, |41' becomes inoperative since it enters the wide part of the slot, and the other ball member enters the narrow part oflits slot and becomes operative. In consequence a given movement of rotation applied to rod |53 produces a reverse rocking of block |39 and imparts an opposite inclination to the roller 13. This reversal of the inclination together with the reversed direction of driving caused by a given rotation of |53 produced by the governer or by the applied force produces a similar speed ratio change in roller 13 and, of course, a similar rotation of gear 65 and with itof sleeve 63 and gear 61.

At the same time that the block Y |39 is being shifted by the change' in direction of the drive,

the pin 89 of each follower roller is being given 25 a rotation through 90 as was explained above. It will be remembered that the pin is held in position by the engagement of its end faces |00 or |02 with the part 99 of the plug 93. When the drive is reversed the greater lever arm of the friction force between the roller and the sleeve as compared with the lesser arm of the frictioniforce between the ends of the pin and the carrier cause the pin to be rotated to a new position in which the other of its end surfaces |00, |02 serves asa stop. In so rotating, the pin 9| is carried bodily so that its left end as in Fig. 1 is rotated below the line c c. When now the rotation of gear 61 occurs under the influence of the changing of driving ratio position of the master roller carrier, the force impressed uponv the ends of the pins 9| is reversed so that an opposite inclination is imroller. This opposite inclination and the reverse direction of drive com-4 bine togive the roller the same tilt and ratio to check too rapid shifting'.

ciated with the brake rodding since it is when,

stopping the car with a brake that this free shift to low is most often desired. The use of the rheostat to operate an instrument to indicate the driving ratio position of the gearing is The limiting means to check the inclination imparted to the master roller and to limit the rotating of the carriers will also be understood without further explanation.

self-evi- Throughout this description no mention has.,

been made of the lubricating features. As in devices of this kind the parts are apertured and pumps are provided to distribute lubricating oil to the several relatively movable parts. Since no lubricating details are being claimed herein it is deemed better to omit from the description the details relating to the provision for lubrication, although some of these details are shown in the drawings. l

' ting driving motion, mechanism whereby a change in driving position of the master roller correl spondingly changes the driving position of the follower roller, supporting means to mount the yfollower roller and mechanism to rotate said supporting means through a predetermined extent, said rotation producing mechanism being operable in response to a reversal of direction of rotation of said follower roller.

2. In power transmitting mechanism having driving and driven discs, a master roller andl a follower roller between said discs for transmitting driving motion, mechanism whereby a change in driving position of the master roller correspondingly changes the driving position of the follower roller, supporting means to mount the follower roller and differential friction means to rotate said supporting means through a predetermined angular extent, the action of Asaid friction means being responsive to a reversal of direction of rotation of said follower roller.

3. In frictional transmission mechanism comprising driving and driven discs, master and follower rollers between said discs for transmitting driving motion, mechanism whereby a change in driving position of the master roller correspondingly changes the driving position of the follower roller, a follower roller sleeve, a pin movably mounted within said sleeve, a second pin carried by the rst pin and pivoted in.said sleeve, said second pin position at an angle to a line joining the points of contact of the roller and discs.

4. -In friction transmission, a single master roller mounted for inclination and tilt, means to incline said master roller, a follower roller mounted forinclinatlon and tilt, mechanical connections independent of said means and operable by thetilting movement of the master roller to change the inclination and tilt of the follower roller. i

5. In frictional transmission comprising a pair of discs and interposed master and follower rollers, mechanism operable from a remote point.

to incline said master roller, said mechanism comprising a sleeve about which said master roller rotates, a pin having a movement relative to said sleeve, a carrier supporting said pin, means whereby said .i carrier is rocked by the tilting movement of the roller from its inclined position, and gearing between said carrier and the follower roller. f' 6. In combination, a reversible driving element, a friction transmission operated thereby and having driving discs and rollers including a master roller and a follower roller, mechanism operable to incline the master roller whereby it rotates about its points of contact with the discs, and means operable by a reversal of direction of rotation of the transmission elements to shift said mechanism to produce opposite directions of inclination corresponding to opposite directions of rotation of the driving .element together with means, independent of the mechanism to incline the master roller, whereby-ratio-changing movements of the master roller produce like movements of the follower roller. i

'1. The invention defined by claim 6, said mechanism including a block mounted to move, connections from said block to said roller to incline said roller, and connections from said block to rollers interposed between said discs, one of said rollers being the master roller and another a follower roller, mechanism to incline the master roller in directions variable with the opposite direction of drive of the input shaft, and means independent of said mechanism and responsive to ratio-changing movements of the master roller to produce like movements of the follower roller.

10. 'I'he invention defined by claim 9, said mechanism comprising a coil spring frictionally engaging one of said shafts, a sleeve surrounding said spring, means on said sleeve to momentarily anchor one end of said spring and to cause said spring to contract as a result of the rotation of the shaft to thereby grip the shaft and rotate said sleeve, and a fixed stop to engage the other end of said spring and render it inoperative after functioning to rotate the sleeve.

11. 'Ihe invention defined by claim 9, said mechanism comprising a coil spring frictionally engaging the output shaft, said spring having terminal abutments, aA sleeve surrounding said spring having end notches to engage the one or the other of said abutments to momentarily anchor the spring whereby the spring becomes wrapped and operates to rotate the sleeve, and a member having fixed abutments to engage the one or the other of the spring abutments afterA the spring has functioned to rotate the sleeve.

12. Ina transmission, a housing, a driving disc, oppositely arranged driven discs and rollers interposed between said discs, one of said rollers being a master roller, means to incline said master roller independently of a movement of the other rollers, carriers supporting said rollers, gearing between said carriers whereby a tilt of one carrier tilts the other carriers, a spider, said carriers being rotatably supported by said spider and said gearing being mounted in fixed relation tosaid spider, said spider being mounted in said housing.

13. In combination, a change speed transmission comprising a driving shaft, a disc rotatable therewith, a driven shaft, driven discs rotatable therewith one on each side of the driving disc, rollers interposed between said discs, each roller being mounted for inclination and tilt, a tube coaxial with said shafts and toothed gearing between each of said rollers and said tube operable when a single master roller is inclined similarly to incline and tilt the other rollers.

I14. In a friction roller transmission, discs and rollers, yielding means to normally maintain pressure between said discs and rollers, torqueresponsive means to supply additional pressure, and yielding means in series with said torque-responsive means to prevent looseness when relieved of load.

JOHN O. ALMEN. JACOB EHRLICH. WINFIELD D. `GOVE. 

